rustup prompt helper

A small command line utility that prints the name of the selected rust toolchain for the current working directory. It helps creating informative command line prompts or scripts where the alternative is piping the output of rustup command through other tools. While that approach is fine it is slower and if you have a busy prompt it can create a noticeable delay every time you press enter.

The output of rustup_prompt_helper should be identical to the following command, as of rustup version 0.6.3

rustup show | tail -n 3 | head -n 1 | cut -d '-' -f 1

Example usage

You can install rustup_prompt_helper with the cargo. Make sure that cargo's binary directory is part of your PATH environment variable.

cargo install rustup_prompt_helper

bash

Here is simple bash prompt example. Place it in your ~/.bashrc and it will show the currently selected toolchain in the prompt if the directory contains a Cargo.toml file.

``` function rusttoolchain { if [ -f Cargo.toml ]; then echo " [rust:$(rustupprompt_helper)]" fi }

PS1='[\u@\h \W]$(rust_toolchain) \$ ' ```

fish

Fish shell uses the fish_prompt function to create a prompt. It can be customized by creating a .config/fish/functions/fish_prompt.fish file.

For a complete example see my fish prompt config.

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.